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            "questionId": "563",
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            "title": "Binary Tree Tilt",
            "titleSlug": "binary-tree-tilt",
            "content": "<p>Given the <code>root</code> of a binary tree, return <em>the sum of every tree node&#39;s <strong>tilt</strong>.</em></p>\n\n<p>The <strong>tilt</strong> of a tree node is the <strong>absolute difference</strong> between the sum of all left subtree node <strong>values</strong> and all right subtree node <strong>values</strong>. If a node does not have a left child, then the sum of the left subtree node <strong>values</strong> is treated as <code>0</code>. The rule is similar if the node does not have a right child.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2020/10/20/tilt1.jpg\" style=\"width: 712px; height: 182px;\" />\n<pre>\n<strong>Input:</strong> root = [1,2,3]\n<strong>Output:</strong> 1\n<strong>Explanation:</strong> \nTilt of node 2 : |0-0| = 0 (no children)\nTilt of node 3 : |0-0| = 0 (no children)\nTilt of node 1 : |2-3| = 1 (left subtree is just left child, so sum is 2; right subtree is just right child, so sum is 3)\nSum of every tilt : 0 + 0 + 1 = 1\n</pre>\n\n<p><strong>Example 2:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2020/10/20/tilt2.jpg\" style=\"width: 800px; height: 203px;\" />\n<pre>\n<strong>Input:</strong> root = [4,2,9,3,5,null,7]\n<strong>Output:</strong> 15\n<strong>Explanation:</strong> \nTilt of node 3 : |0-0| = 0 (no children)\nTilt of node 5 : |0-0| = 0 (no children)\nTilt of node 7 : |0-0| = 0 (no children)\nTilt of node 2 : |3-5| = 2 (left subtree is just left child, so sum is 3; right subtree is just right child, so sum is 5)\nTilt of node 9 : |0-7| = 7 (no left child, so sum is 0; right subtree is just right child, so sum is 7)\nTilt of node 4 : |(3+5+2)-(9+7)| = |10-16| = 6 (left subtree values are 3, 5, and 2, which sums to 10; right subtree values are 9 and 7, which sums to 16)\nSum of every tilt : 0 + 0 + 0 + 2 + 7 + 6 = 15\n</pre>\n\n<p><strong>Example 3:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2020/10/20/tilt3.jpg\" style=\"width: 800px; height: 293px;\" />\n<pre>\n<strong>Input:</strong> root = [21,7,14,1,1,2,2,3,3]\n<strong>Output:</strong> 9\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li>The number of nodes in the tree is in the range <code>[0, 10<sup>4</sup>]</code>.</li>\n\t<li><code>-1000 &lt;= Node.val &lt;= 1000</code></li>\n</ul>\n",
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            "exampleTestcases": "[1,2,3]\n[4,2,9,3,5,null,7]\n[21,7,14,1,1,2,2,3,3]",
            "categoryTitle": "Algorithms",
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                    "name": "Tree",
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                    "name": "Depth-First Search",
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                    "lang": "C++",
                    "langSlug": "cpp",
                    "code": "/**\n * Definition for a binary tree node.\n * struct TreeNode {\n *     int val;\n *     TreeNode *left;\n *     TreeNode *right;\n *     TreeNode() : val(0), left(nullptr), right(nullptr) {}\n *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}\n *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}\n * };\n */\nclass Solution {\npublic:\n    int findTilt(TreeNode* root) {\n        \n    }\n};",
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                {
                    "lang": "Java",
                    "langSlug": "java",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     int val;\n *     TreeNode left;\n *     TreeNode right;\n *     TreeNode() {}\n *     TreeNode(int val) { this.val = val; }\n *     TreeNode(int val, TreeNode left, TreeNode right) {\n *         this.val = val;\n *         this.left = left;\n *         this.right = right;\n *     }\n * }\n */\nclass Solution {\n    public int findTilt(TreeNode root) {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Python",
                    "langSlug": "python",
                    "code": "# Definition for a binary tree node.\n# class TreeNode(object):\n#     def __init__(self, val=0, left=None, right=None):\n#         self.val = val\n#         self.left = left\n#         self.right = right\nclass Solution(object):\n    def findTilt(self, root):\n        \"\"\"\n        :type root: TreeNode\n        :rtype: int\n        \"\"\"\n        ",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Python3",
                    "langSlug": "python3",
                    "code": "# Definition for a binary tree node.\n# class TreeNode:\n#     def __init__(self, val=0, left=None, right=None):\n#         self.val = val\n#         self.left = left\n#         self.right = right\nclass Solution:\n    def findTilt(self, root: Optional[TreeNode]) -> int:\n        ",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "C",
                    "langSlug": "c",
                    "code": "/**\n * Definition for a binary tree node.\n * struct TreeNode {\n *     int val;\n *     struct TreeNode *left;\n *     struct TreeNode *right;\n * };\n */\n\n\nint findTilt(struct TreeNode* root){\n\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "C#",
                    "langSlug": "csharp",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     public int val;\n *     public TreeNode left;\n *     public TreeNode right;\n *     public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {\n *         this.val = val;\n *         this.left = left;\n *         this.right = right;\n *     }\n * }\n */\npublic class Solution {\n    public int FindTilt(TreeNode root) {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "JavaScript",
                    "langSlug": "javascript",
                    "code": "/**\n * Definition for a binary tree node.\n * function TreeNode(val, left, right) {\n *     this.val = (val===undefined ? 0 : val)\n *     this.left = (left===undefined ? null : left)\n *     this.right = (right===undefined ? null : right)\n * }\n */\n/**\n * @param {TreeNode} root\n * @return {number}\n */\nvar findTilt = function(root) {\n    \n};",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Ruby",
                    "langSlug": "ruby",
                    "code": "# Definition for a binary tree node.\n# class TreeNode\n#     attr_accessor :val, :left, :right\n#     def initialize(val = 0, left = nil, right = nil)\n#         @val = val\n#         @left = left\n#         @right = right\n#     end\n# end\n# @param {TreeNode} root\n# @return {Integer}\ndef find_tilt(root)\n    \nend",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Swift",
                    "langSlug": "swift",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     public var val: Int\n *     public var left: TreeNode?\n *     public var right: TreeNode?\n *     public init() { self.val = 0; self.left = nil; self.right = nil; }\n *     public init(_ val: Int) { self.val = val; self.left = nil; self.right = nil; }\n *     public init(_ val: Int, _ left: TreeNode?, _ right: TreeNode?) {\n *         self.val = val\n *         self.left = left\n *         self.right = right\n *     }\n * }\n */\nclass Solution {\n    func findTilt(_ root: TreeNode?) -> Int {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Go",
                    "langSlug": "golang",
                    "code": "/**\n * Definition for a binary tree node.\n * type TreeNode struct {\n *     Val int\n *     Left *TreeNode\n *     Right *TreeNode\n * }\n */\nfunc findTilt(root *TreeNode) int {\n    \n}",
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                    "lang": "Scala",
                    "langSlug": "scala",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode(_value: Int = 0, _left: TreeNode = null, _right: TreeNode = null) {\n *   var value: Int = _value\n *   var left: TreeNode = _left\n *   var right: TreeNode = _right\n * }\n */\nobject Solution {\n    def findTilt(root: TreeNode): Int = {\n        \n    }\n}",
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                {
                    "lang": "Kotlin",
                    "langSlug": "kotlin",
                    "code": "/**\n * Example:\n * var ti = TreeNode(5)\n * var v = ti.`val`\n * Definition for a binary tree node.\n * class TreeNode(var `val`: Int) {\n *     var left: TreeNode? = null\n *     var right: TreeNode? = null\n * }\n */\nclass Solution {\n    fun findTilt(root: TreeNode?): Int {\n        \n    }\n}",
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                {
                    "lang": "Rust",
                    "langSlug": "rust",
                    "code": "// Definition for a binary tree node.\n// #[derive(Debug, PartialEq, Eq)]\n// pub struct TreeNode {\n//   pub val: i32,\n//   pub left: Option<Rc<RefCell<TreeNode>>>,\n//   pub right: Option<Rc<RefCell<TreeNode>>>,\n// }\n// \n// impl TreeNode {\n//   #[inline]\n//   pub fn new(val: i32) -> Self {\n//     TreeNode {\n//       val,\n//       left: None,\n//       right: None\n//     }\n//   }\n// }\nuse std::rc::Rc;\nuse std::cell::RefCell;\nimpl Solution {\n    pub fn find_tilt(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {\n        \n    }\n}",
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                {
                    "lang": "PHP",
                    "langSlug": "php",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode {\n *     public $val = null;\n *     public $left = null;\n *     public $right = null;\n *     function __construct($val = 0, $left = null, $right = null) {\n *         $this->val = $val;\n *         $this->left = $left;\n *         $this->right = $right;\n *     }\n * }\n */\nclass Solution {\n\n    /**\n     * @param TreeNode $root\n     * @return Integer\n     */\n    function findTilt($root) {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
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                    "lang": "TypeScript",
                    "langSlug": "typescript",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode {\n *     val: number\n *     left: TreeNode | null\n *     right: TreeNode | null\n *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {\n *         this.val = (val===undefined ? 0 : val)\n *         this.left = (left===undefined ? null : left)\n *         this.right = (right===undefined ? null : right)\n *     }\n * }\n */\n\nfunction findTilt(root: TreeNode | null): number {\n\n};",
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                    "lang": "Racket",
                    "langSlug": "racket",
                    "code": "; Definition for a binary tree node.\n#|\n\n; val : integer?\n; left : (or/c tree-node? #f)\n; right : (or/c tree-node? #f)\n(struct tree-node\n  (val left right) #:mutable #:transparent)\n\n; constructor\n(define (make-tree-node [val 0])\n  (tree-node val #f #f))\n\n|#\n\n(define/contract (find-tilt root)\n  (-> (or/c tree-node? #f) exact-integer?)\n\n  )",
                    "__typename": "CodeSnippetNode"
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                    "lang": "Erlang",
                    "langSlug": "erlang",
                    "code": "%% Definition for a binary tree node.\n%%\n%% -record(tree_node, {val = 0 :: integer(),\n%%                     left = null  :: 'null' | #tree_node{},\n%%                     right = null :: 'null' | #tree_node{}}).\n\n-spec find_tilt(Root :: #tree_node{} | null) -> integer().\nfind_tilt(Root) ->\n  .",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Elixir",
                    "langSlug": "elixir",
                    "code": "# Definition for a binary tree node.\n#\n# defmodule TreeNode do\n#   @type t :: %__MODULE__{\n#           val: integer,\n#           left: TreeNode.t() | nil,\n#           right: TreeNode.t() | nil\n#         }\n#   defstruct val: 0, left: nil, right: nil\n# end\n\ndefmodule Solution do\n  @spec find_tilt(root :: TreeNode.t | nil) :: integer\n  def find_tilt(root) do\n\n  end\nend",
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            "hints": [
                "Don't think too much, this is an easy problem. Take some small tree as an example.",
                "Can a parent node use the values of its child nodes? How will you implement it?",
                "May be recursion and tree traversal can help you in implementing.",
                "What about postorder traversal, using values of left and right childs?"
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